wattisit

hi guys and gals, i have the need of the expert knowledge of you lot again,
I have this fish in my tank that I need the name of it so I can pass it on to others as its a sand shifter, and because I have an all rock tank, its causing nightmares and landslides

 

i think its an engineer goby

 

Engineer goby/convict worm blennys are white and black not yellow and black.. Also, they are very eel like. Does the fish look like an eel or does it have noticable finnage?

 

damd you lot are fast

many thanks, does this coincide with it being aroud a foot long?
and can swim backwards, but you can see fins on the side like a fish but it has like a spoiler right down the back of it

 

googled it and yes ita an engineer goby, but the neon speciemen